An electrical conductor that is temporarily implanted (< 30 days) beneath the surface of the brain to stimulate the brain or to record the brain's electrical activity (with more precise localization than a scalp electrode). It is typically a fine, flexible plastic device attached to wires that carry currents from deep and superficial brain structures. The wires are connected to recording, monitoring, or stimulation/response devices [e.g., electroencephalograph (EEG), evoked-potential recorder, stimulator]. The implant is particularly helpful in determining site of origin in temporal and frontal lobe epilepsy. This is a single-use device.